EMC Corporation Corporate Headquarters: Hopkinton, MA 01748
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9103 1-
508-
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1000 www.EMC.comMicrosoft Windows Version
Release 6.4
Technical Product Overview
P/N 300-007-802
REV A01
Published March, 2009
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EMC DiskXtender Release 6.4 Microsoft Windows Version Technical Product Overview 3
Preface
Chapter 1
The DiskXtender Advantage
Seamless extension of disk space ... 16
Full NTFS compatibility ... 16
Native Windows network connectivity and security ... 17
Automated file management ... 18
Flexible support for back end storage... 19
Hardware scalability ... 19
Automated media management... 20
Offline media support... 20
Chapter 2
Architecture and Requirements
DiskXtender architecture ... 22DiskXtender components ... 24
User machines ... 24
File System Manager ... 24
Media services... 25
License Server ... 28
DiskXtender Search Module ... 29
System requirements ... 30
Security requirements ... 31
Chapter 3
File Management
Supported file types ... 36International character support... 37
Path and filename length limitations... 37
File stream support... 38
Encryption ... 38
Microsoft Windows offline files... 38
Microsoft Windows DFS links ... 39
Migrating files to media... 40
File migration models ... 40
Customizing file migration ... 42
Purging files... 44
Purge rules... 45
Purging files during background scans... 46
Purging files immediately after migration ... 46
Purging files during DVD-R finalization... 46
Fetching files ... 47 Prefetch ... 47 Direct Read... 47 Editing files ... 48 Deleting files ... 49 Delete rules ... 50 Recycler ... 50
Indexing and searching for files... 52
Indexing files ... 52
Searching for files... 52
Supported file types for indexing ... 53
DiskXtender file management through Windows Explorer ... 54
Chapter 4
Media Management
EMC Centera... 56Virtual media ... 57
Content-addressable storage ... 58
Compliance through retention and audit... 62
Replication ... 63
Network-attached storage... 67
Standard NAS... 67
Aggregate NAS ... 67
Retained NAS ... 68
Limitations for filepath lengths... 69
Creating the shares for NAS media... 70
Removable media... 73
MediaStor ... 73
Sun StorageTek ACSLS... 75
Managing the removable media lifecycle... 77
Tivoli Storage Manager ... 81
Chapter 5
Monitoring DiskXtender
Monitoring service events, errors, and warnings... 84Monitoring file activity... 84
Monitoring media ... 85
Media status indicators ... 85
Media task queue ... 85
Media logs ... 85 Media properties ... 85 Monitoring licensing... 86 Reports ... 86 Audit logs ... 87 Remote administration ... 87
Chapter 6
Backup and Recovery
Developing a backup strategy... 90EMC DiskXtender Release 6.4 Microsoft Windows Version Technical Product Overview 5
Backing up NAS... 93
Backing up TSM... 94
Backing up the DiskXtender server ... 95
Protecting against accidental file deletion... 96
Chapter 7
Interoperability
DiskXtender as an application back end ... 98Documentum ApplicationXtender ... 98
Custom integration through the DiskXtender SDK ... 98
High availability ... 99
AutoStart... 99
PowerPath... 99
Replication ... 101
Anti-virus software interoperability ... 102
DiskXtender on VMware... 102
Clustering DiskXtender on VMware ... 102
VMotion support ... 103
Index
EMC DiskXtender Microsoft Windows Version Release 6.4 Technical Product Overview 7
Title Page
1 DiskXtender architecture ... 22
2 File System Manager Administrator ... 25
3 MediaStor Administrator... 27
4 Standard migration ... 40
5 Multi-target migration... 40
6 Tiered migration... 41
7 EMC Centera C-Clip for a DiskXtender file ... 58
8 Embedded BLOB for a file stored on EMC Centera... 60
9 Separate CDF and BLOB for a file stored on EMC Centera... 60
10 Tiered migration... 68
11 DiskXtender with NAS... 71
12 File System Manager with MediaStor ... 74
13 DiskXtender with ACSLS... 76
EMC DiskXtender Microsoft Windows Version Release 6.4 Technical Product Overview 9
Title Page
1 Supported removable media types... 19
2 Supported media services... 26
3 Minimum and Recommended Hardware Requirements for DiskXtender ... 30
4 DiskXtender user groups ... 32
5 Product interoperability and foreign-language character support... 37
6 Icons for files on the extended drive ... 44
7 File edit and rename capabilities by media type ... 48
8 File delete capabilities by media type ... 49
9 Types of retention ... 62
10 NAS media types... 67
11 Supported removable media types... 73
12 FIle system support by media type ... 79
13 Subsystems for the OTG file system... 79
14 UDF file systems... 80
15 Toolbar icons for events, warnings, and errors ... 84
16 Media status indicated by color ... 85
17 Reports ... 86
EMC DiskXtender Release 6.4 Microsoft Windows Version Technical Product Overview 11
As part of an effort to improve and enhance the performance and capabilities of its product lines, EMC periodically releases revisions of its hardware and software. Therefore, some functions described in this document may not be supported by all versions of the software or hardware currently in use. For the most up-to-date information on product features, refer to your product release notes.
If a product does not function properly or does not function as described in this document, please contact your EMC representative.
Audience This Technical Product Overview is intended for technical staff and managers, including:
◆ IT managers and IT staff ◆ Development managers ◆ Engineers
◆ System administrators
Readers of this document are expected to be familiar with the following topics: ◆ Microsoft Windows network administration
◆ Storage media and hardware device management
Related documentation
Related documents include:
◆ EMC DiskXtender Microsoft Windows Version Release 6.4 Installation Guide
◆ EMC DiskXtender Microsoft Windows Version Release 6.4 Administration Guide
◆ EMC DiskXtender Microsoft Windows Version Release 6.4 Release Notes
◆ EMC DiskXtender Search Module Release 1.1 Installation Guide
◆ EMC DiskXtender Search Module Release 1.2 Release Notes
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EMC DiskXtender Release 6.4 Microsoft Windows Version Technical Product Overview 13
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The DiskXtender Advantage 15
The following topics provide an introduction to and describe the benefits of EMC DiskXtender for Windows:
◆ Seamless extension of disk space ... 16 ◆ Automated file management... 18 ◆ Flexible support for back end storage ... 19
The DiskXtender
Advantage
Seamless extension of disk space
EMC® DiskXtender® for Windows is so named because it extends the amount of space on a server’s local New Technology File System (NTFS) volume, or hard drive partition. This can either be a volume physically located on the DiskXtender server or a fibre-connected drive that has been mapped as a local drive.
DiskXtender extends the amount of space on a drive by migrating files from the drive to external storage media, while maintaining the appearance that the files are still on the drive. A drive that has been extended through DiskXtender is called an extended
drive.
The management of files on the extended drive through DiskXtender is actually a two-part process. Those two parts are referred to as a move and a purge and can be performed separately or simultaneously.
In DiskXtender, a move is actually a copy. When DiskXtender moves a file to media, it is really copying the file data out to media and adding extended attribute information to the file on the drive. The file is then managed by DiskXtender, and the data resides both on the extended drive and on the media.
After file data is moved to storage media, that data can be removed, or purged, from the extended drive, which frees that space for additional files. The purging of a file removes the file data from the drive, and leaves behind a file tag on the drive. The data then resides only on the media.
The file tag serves two purposes:
◆ It allows the file to appear as if it still resides on the drive so that users can easily find it.
◆ It contains the extended file attribute information that DiskXtender needs to manage and retrieve the file from media.
To a user who retrieves files from a drive extended by DiskXtender, all files appear to be present, regardless of whether the file data is on the drive or only on storage media. When the user requests the files, DiskXtender accesses the media where the files are stored and retrieves the file data, and displays it for the user. This file retrieval process is called a fetch.
Full NTFS compatibility
Since DiskXtender uses the NTFS file system as the gateway to its remote storage management functions, all native features of NTFS are supported, including support for:
◆ Long filenames (up to 259 characters) ◆ Filenames with Unicode characters ◆ Folder and file-level security ◆ Offline files
Regardless of the media type that is being used for remote storage, full security can be applied to any file or folder on an extended drive, even if the storage media itself does not support Microsoft Windows security (for example, magneto-optical WORM or tape).
Seamless extension of disk space 17
Native Windows network connectivity and security
DiskXtender does not interfere with Windows networking. Users that access an extended drive, usually through network shares, can connect by using any installed transports and protocols.
DiskXtender does not interfere with Windows security either. Users that access an extended drive are authenticated through native Windows security. The operating system manages security at all levels.
Automated file management
DiskXtender automates the migration of files to media by using a rule-based system. Rather than just migrate all files to media without distinction between the files, you can select which files should be moved to what types and pieces of media, and when those files are moved.
After file data is moved to storage media, automatic file purge options can remove the file data from the drive, and leave behind a file tag so that the file can be retrieved when necessary.
File purging can occur:
◆ Immediately for all files, as soon as they are moved to media ◆ When extended drive disk space is needed
◆ When the files meet other criteria, such as a certain age
If necessary, you can protect migrated files from being edited or deleted during a specified time period. This protection is called file retention, and is required in some environments to comply with government and organizational regulations. Retention is available if you are migrating files from DiskXtender to one of the following devices:
◆ EMC Centera®
◆ EMC Celerra® with the File-Level Retention (FLR) file system ◆ Network Appliance (NetApp) NAS device with SnapLock software
When you apply retention, the files are protected both on the extended drive and on the storage hardware device.
In some instances, you may also want to delete files completely when they are no longer of use. You can either delete files manually (for example, through Windows Explorer), or you can delete files automatically through DiskXtender by using rule-based criteria.
When you delete a file from the extended drive, the file is also deleted from any associated storage media, if the media allows it.
Flexible support for back end storage 19
Flexible support for back end storage
DiskXtender supports many high-capacity storage media types, including several removable media and disk-based storage options.
Table 1 on page 19 provides details on the supported removable media types.
These media types are supported through a wide variety of hardware devices. For a complete list, refer to the DiskXtender for Windows Supported Device List, available on the EMC Powerlink® website.
Disk-based storage options include EMC CLARiiON®, and Celerra, as well as many other Redundant Array of Independent Disks (RAIDs) and network-attached storage (NAS) devices. Essentially, a server with a network share that is available to
DiskXtender can be used as storage media. DiskXtender considers all of these shared devices to be NAS media.
DiskXtender also supports the use of an EMC Centera content-addressed storage (CAS) system, the first magnetic disk-based WORM device. DiskXtender and EMC Centera are tightly integrated to optimize file storage and retrieval performance. Several DiskXtender file migration and retention features are designed specifically to take advantage of the features available with an EMC Centera device.
DiskXtender transparently manages data movement between the extended drive and the storage media. Communication with the hardware devices that contain the storage media is established through the creation of DiskXtender media services. DiskXtender transfers files to the media provided by the media services, and sends requests for pieces of media to the media services as needed.
DiskXtender manages all functions related to the transfer of information to and from media, such as the migration and retrieval of files. The only role a media service plays is to provide access to the media so that DiskXtender can work with it. For a media service that provides access to removable media, this means that the service places the requested media into a drive or prompts the administrator of the media service to insert the appropriate piece of media. For a media service that provides access to disk-based devices, this means that the service provides access to a place where the data is written.
You can use any or all of these media types with a single DiskXtender installation.
Hardware
scalability
With DiskXtender, hardware can grow with your storage needs, and you do not need to reconfigure or reformat the extended drives. DiskXtender interfaces with the software that manages the storage devices. The devices are completely independent of the extended drives they support, even though DiskXtender controls the media in those devices. If you are using removable media, you can change hardware and relocate media without affecting the files on your extended drive or the ability of DiskXtender to find files on the storage media.
Table 1 Supported removable media types
Media type Details
Tape and tape-WORM LTO, SDLT, DLT, SAIT, AIT, 9840, and 9940
DVD DVD-R, DVD-RAM, and DVD-ROM
DiskXtender stores an internal inventory of all online and offline media in the system. This inventory system means that removable media is not dedicated to a specific hardware device. When hardware configuration or removable media locations change, the internal inventory is automatically updated so that DiskXtender always knows where media is located.
When file migration or retrieval is required, DiskXtender uses its internal inventory to automatically find the proper media for the requested file.
Automated media
management
DiskXtender can automatically prepare media for file migration when it is needed, as well as reclaim space that is no longer used on some media types.
If you are using removable media, DiskXtender can automatically format, label, and assign media for file migration from a group of blank media. You can also reclaim space on removable media by compacting it when wasted space exceeds a certain percentage. When you compact a piece of media, active files on the media (current versions of written files and files not marked for deletion) are written back to the extended drive and are remigrated to another piece of eligible media. You can then reformat the compacted media so that it can be used again. Compaction optimizes media usage even if file deletions are frequent.
If you are using an EMC Centera device, DiskXtender can automatically create the "virtual" media that DiskXtender uses to simulate divisions of an EMC Centera cluster. The use of virtual media enables you to take advantage of the flexible file migration features available in DiskXtender.
If you are using DVD-R media, DiskXtender can automatically finalize the media when it is full. Finalization closes the media, which prevents the writing of any more files to the media. Finalization also increases the stability of the media so that data is better protected.
Offline media
support
Offline media support is very important for large systems with limited hardware resources and large storage requirements. DiskXtender fully supports offline media. With DiskXtender, media can be online or offline. When online, users can access any file on the media. If media is taken offline and a file is requested that is not on the extended drive, the user receives an error message and the DiskXtender system administrator is notified that the requested media must be mounted.
One important benefit of DiskXtender offline media support is that the files on your extended drive are not affected by the state of the media. Unlike other products, where files disappear when media is taken offline, DiskXtender maintains file and folder information whether the media is online or offline. This enables you to take hardware devices offline for maintenance without concerns about
whetherDiskXtender will be able to find the files or media when the device is set online again. Users and applications can always see their files on an extended drive. In addition, if you know in advance what media will be offline for a period of time, you can copy certain files from the media back to the extended drive. This prefetch feature ensures that files are available for user requests even when media is offline.
Architecture and Requirements 21
The following topics introduce the DiskXtender architecture and provide the minimum system requirements for installing and using DiskXtender:
◆ DiskXtender architecture ... 22 ◆ DiskXtender components... 24 ◆ System requirements ... 30 ◆ Security requirements... 31
Architecture and
Requirements
DiskXtender architecture
Figure 1 on page 22 illustrates the basic components of a DiskXtender for Windows system, which can be set up on several computers to avoid the bottleneck of an architecture with a single server and multiple clients.
Figure 1 DiskXtender architecture
Users save files to and retrieve files from one or more DiskXtender extended drives. The extended drives are NTFS volumes on a Microsoft Windows server. The DiskXtender File System Manager component, which is the main component of the DiskXtender system, is installed on the server.
GEN-000939 Workstations H:\NTFS Retrieving and saving files Extended drives G:\NTFS
FIle System Manager installed
RPC connection
Standard network connection TCP/IP connection MediaStor installed DiskXtender server NAS device Library and drive devices EMC Centera CAS system MediaStor server
DiskXtender architecture 23
File System Manager monitors activity on the extended NTFS volumes, and manages all functions related to the transfer of information to and from media, such as the migration and retrieval of files. Communication with the hardware devices that contain the storage media is established through the creation of DiskXtender media
services. DiskXtender transfers files to the media provided by the media services, and
sends requests for pieces of media to the media services as needed. The only role a media service plays is to provide access to the media so that DiskXtender can work with it.
DiskXtender components
The DiskXtender architecture consists of the following components: ◆ “User machines” on page 24
◆ “File System Manager” on page 24 ◆ “Media services” on page 25 ◆ “License Server” on page 28
◆ “DiskXtender Search Module” on page 29
User machines
All users that can connect to an NTFS volume can store and access files on a DiskXtender extended drive.DiskXtender can manage files written to the extended drive from user machines that use NTFS or File Allocation Table (FAT) because both are Microsoft Windows native file systems. DiskXtender also supports streamed files from user machines that use a network file system (NFS), such as a UNIX/Linux file system.
File System
Manager
DiskXtender File System Manager is the data mover for the DiskXtender product suite. File System Manager moves files from the extended drive to storage media, and retrieves files when they are requested.
The File System Manager program is installed on the server connected to or containing the NTFS volumes to be extended. This server is considered the
DiskXtender server. When you install File System Manager, the DiskXtender service, the File System Manager Administrator interface, and a filter driver are installed.
Service DiskXtender functions as a Windows service rather than as a user-mode application. As a Windows service, DiskXtender can continue to be active even after you log out of Windows, as long as the computer is still running.
Administrator interface
Configuration of file migration, purging, deletion, indexing, and other system options is performed by using the File System Manager Administrator interface, which is illustrated in Figure 2 on page 25.
DiskXtender components 25
Figure 2 File System Manager Administrator
Filter driver The DiskXtender filter driver keeps track of all files created, requested, edited, deleted, and indexed on the extended drive. This driver ensures that all the qualified files are moved to storage media, purged, fetched, deleted, and indexed when appropriate.
When a file on the extended drive is saved or changed, the filter driver analyzes the file to determine if action must be taken.
The filter driver analyzes all files, including those not managed by DiskXtender. If there are frequently changing files (such as email files) on the extended drive, the filter driver must monitor those files. This can cause a reduction in system
performance. As a result, the extended drive should be reserved for files that should be managed by DiskXtender.
Media services
Communication with the hardware devices that contain the storage media is established through the creation of DiskXtender media services. DiskXtender transfers files to the media provided by the media services, and sends requests for pieces of media to the media services as needed.DiskXtender manages all functions related to the transfer of information to and from media, such as the migration and retrieval of files. The only role a media service plays is to provide access to the media so that DiskXtender can work with it.
For a media service that provides access to removable media, this means that the service places the requested media into a drive or prompts the administrator of the media service to insert the appropriate piece of media.
For a media service that provides access to disk-based devices, this means that the service provides access to a place where the data is written.
Table 2 on page 26 describes the media services that are supported by DiskXtender, as well as the media types supported by the media service.
MediaStor DiskXtender MediaStor™ is a media service program that is provided automatically with the DiskXtender product suite. MediaStor provides comprehensive drive and library management capabilities for retrieving, mounting, and dismounting removable media in a variety of hardware devices.
MediaStor functions as a Microsoft Windows service and can be configured through an Administrator interface, as illustrated in Figure 3 on page 27.
Table 2 Supported media services
Media service Abbreviated name
Media types supported through the media services
DiskXtender MediaStor MediaStor • Magneto-optical (MO)
• Ultra Density Optical (UDO) • MO WORM • UDO WORM • Tape • Tape-WORM • DVD-R • DVD-RAM • DVD-ROM
EMC Centera EMC Centera “Virtual” media defined in DiskXtender to
simulate divisions of the EMC Centera cluster
Network-attached storage NAS “Virtual” media defined in DiskXtender that correspond to shares on a NAS device
IBM Tivoli Storage Manager TSM “Virtual” media defined in DiskXtender to simulate divisions of the disk on the TSM server
Sun StorageTek Automated Cartridge System Library Software (ACSLS)
DiskXtender components 27
Figure 3 MediaStor Administrator
“MediaStor” on page 73 provides additional details on the features available through MediaStor.
EMC Centera The EMC Centera media service provides access to an EMC Centera
content-addressed storage (CAS) system, the first magnetic disk-based WORM device.
When you configure an EMC Centera media service in DiskXtender, you create a connection between DiskXtender and the access nodes of an EMC Centera cluster. EMC Centera media in DiskXtender is considered virtual, meaning that a piece of media in DiskXtender does not correspond to a physical piece of media, such as a tape cartridge. Instead, the virtual media is designed to simulate divisions of an EMC Centera cluster. Creation of EMC Centera media in DiskXtender enables you to take advantage of the flexible file migration features available in DiskXtender.
DiskXtender and EMC Centera are tightly integrated to optimize file storage and retrieval performance. Several DiskXtender file migration and retention features are designed specifically to take advantage of the features available with an EMC Centera device. “EMC Centera” on page 56 provides additional details.
Network-attached storage
NAS media in DiskXtender are network shares on disk-based storage devices. These shares can be located on a server hard drive or on any network appliance that provides share-level access to storage, such as a CLARiiON or Celerra device. Each DiskXtender installation can have only one NAS media service. However, you can create as many pieces of NAS media for that media service as you want, and each piece of media can write to a different share on a different device.
“Network-attached storage” on page 67 provides additional details on the use of NAS with DiskXtender.
IBM Tivoli Storage Manager
If you are using TSM, you can leverage the storage management capabilities of TSM with DiskXtender. When you configure a TSM media service in DiskXtender, files on the extended drive can be moved to a TSM server. TSM can subsequently move the files to storage devices that are managed by the TSM server.
TSM media in DiskXtender is considered virtual, meaning that a piece of media in DiskXtender does not correspond to a physical piece of media in the TSM system, such as a tape cartridge. Instead, the virtual media is designed to simulate divisions of the larger repository (the TSM server). Creation of TSM media in DiskXtender enables you to take advantage of the flexible file migration features available in DiskXtender.
The TSM server manages the actual physical removable media, so that tasks like formatting, labeling, and copying media are performed by TSM rather than by DiskXtender.
“Tivoli Storage Manager” on page 81 provides additional details on the use of TSM with DiskXtender.
Details on the supported versions of the TSM server and client products are listed in the EMC Information Protection Software Compatibility Guide available on the Powerlink website.
Sun StorageTek ACSLS If you have already invested in ACSLS, you can use DiskXtender to migrate files from a Microsoft Windows server to tape media in libraries managed by the ACSLS server. ACSLS is a UNIX-based device management product that manages Sun StorageTek tape libraries and provides device-sharing capability between applications.
A SCSI cable connects the DiskXtender server and one or more drives in the Sun StorageTek library. When you configure an ACSLS media service in DiskXtender, you designate the connected drives as the drives that should be used by DiskXtender. Other servers cannot access that drive.
Certain pieces of media in the ACSLS system are assigned to DiskXtender by using ACSLS.
When DiskXtender requires a particular piece of media, DiskXtender requests that media from ACSLS. ACSLS retrieves the media and places it in the drive connected to the DiskXtender server. DiskXtender then communicates directly with the drive, and initiates all media-related tasks without any involvement from ACSLS.
“Sun StorageTek ACSLS” on page 75 provides additional details on the use of ACSLS with DiskXtender.
Details on the supported versions of the ACSLS and LibAttach products are listed in the EMC Information Protection Software Compatibility Guide available on the Powerlink website.
License Server
DiskXtender licensing information is managed by the EMC Xtender Solutions® License Server program. The License Server program is included on the DiskXtender installation CD and can be installed on a DiskXtender server, or on a separate computer that is visible to the DiskXtender server through the network.The License Server program also manages licensing information for several other EMC products, including EMC Documentum® ApplicationXtender® and EMC EmailXtender®.
DiskXtender components 29
The computer on which you install License Server depends on the environment: ◆ If License Server manages only a DiskXtender license for a single DiskXtender
installation, then it can be safely installed on the DiskXtender server without any significant impact on performance.
◆ If License Server manages a DiskXtender license for multiple DiskXtender installations, then you may want to install it on a separate computer that is accessible to all of the DiskXtender servers.
◆ If License Server manages licenses for both DiskXtender and multiple
ApplicationXtender clients, then it should be installed on a separate computer to avoid any impact on DiskXtender server performance.
DiskXtender Search
Module
The DiskXtender Search Module is optional software that works exclusively with DiskXtender for Windows release 6.2 and later. The DiskXtender Search Module software enables you to index files that are stored on one or more extended drives, create search queries, and then view files returned by the search query.
The DiskXtender Search Module includes two primary components:
◆ Index and Search Engine (ISE) — The ISE manages content indexing and is installed on a separate server from the DiskXtender server. A single ISE server can index files from as many as 10 DiskXtender servers. Each DiskXtender server should manage no more than five extended drives.
◆ User interface — The user interface provides a way to search a collection of indexes for files managed by DiskXtender, and then to view the search results. It also enables you to perform several important administrative tasks on the ISE, such as index preparation tasks and the addition of index file storage.
The user interface can be installed on the ISE server. It can also be installed on a different computer, so that you can connect remotely to perform searches and administrative tasks.
Note: The DiskXtender Search Module is not intended for end-user searches of data. Only users with administrative privileges on the ISE server or on the domain can view search results. Search capabilities should only be allowed to select individuals, such as a security officer or IT manager who has the authority or job responsibility for the retrieval of the company’s data. You can install the DiskXtender Search Module along with DiskXtender in a new environment. You can also install the DiskXtender Search Module in an environment where DiskXtender is already managing files.
The ISE can index new files that are saved to the extended drive, as well as files that were on the extended drive prior to the DiskXtender or DiskXtender Search Module installation.
System requirements
The Windows servers on which you install DiskXtender and MediaStor should meet the requirements listed in Table 3 on page 30.
The DiskXtender installation guide provides in-depth details on system requirements.
The latest Windows operating system versions, service packs, and hot fixes that are certified for use with DiskXtender are listed in the EMC Information Protection Software
Compatibility Guide available on the Powerlink website.
Table 3 Minimum and recommended hardware requirements for DiskXtender
Requirement Minimum Recommended
Processora 1.3 GHz 2.8 GHz
Memory 1 GB 2 GB
Free space on the system drive 200 MB 20% free
Total size of the extended drive 100 MB 10 GB
Operating system • Windows 2003 Standard or Enterprise Edition with SP2 (x64)
• Windows Storage Server 2003 (x64)
• Windows Server 2008 Standard or Enterprise Edition with SP1 (x64)
a. DiskXtender is supported on x86 platforms running a supported version of the Windows operating system, including Intel and AMD x86 processors. Neither Itanium processors nor Windows operating systems for Itanium-based architectures are supported.
Security requirements 31
Security requirements
DiskXtender should always be installed in a trusted Microsoft Windows domain and on a dedicated server to maximize a secure deployment. In addition, the DiskXtender installation should be protected from access from unauthorized users. Local
administrators and users on the DiskXtender server should be limited to highly trusted individuals.
DiskXtender and its components provide several mechanisms to ensure the security of the DiskXtender system. However, each environment is unique and may provide unforeseen security risks. All security issues that are reported will be given a high priority, with a goal of addressing the issue within 30 days.
The following sections discuss the security mechanisms available with DiskXtender.
Service account security requirements
The user account that DiskXtender uses to log on as a service must be a member of the local Administrators group on the DiskXtender server. This account must also have the Log on as a service privilege. Because DiskXtender uses the account entered during installation to log on to the DiskXtender service, this privilege is added to that account during installation.
The service account must have full access rights to all files in all media folders in order to manage the files. If the service account does not have access to the files, it assumes that there are no files to process. There are no error messages or other indications that DiskXtender is not managing the files.
Depending on the environment, the following additional requirements may apply: ◆ If you are using the MediaStor media service, then you must add the DiskXtender
service account to the MsAdministrators group on the MediaStor server.
◆ If you are planning to index files by using the DiskXtender Search Module, then you must add the DiskXtender service account to the DxIndexers group on the ISE server.
Controlling access to the DiskXtender configuration
To assist in the prevention of unauthorized users from connecting to DiskXtender servers and configuring the system, the user groups listed in Table 4 on page 32 are created on the DiskXtender server during installation.
Note: On the MediaStor server, the groups are MsAdministrators, MsUsers, MsSecurityAdmins, and MsMonitors.
To add or remove users from these groups, use Microsoft Windows group
management functions. When DiskXtender is installed in a Microsoft clustering or AutoStart™ environment, changes or additions to the security groups must be configured on each of the servers in the cluster or AutoStart domain.
Table 4 DiskXtender user groups
Group name Description
DxAdministrators Members of the DxAdministrators group can log onto the DiskXtender server, either locally or by using a Remote Administrator installation, and perform all functions except for editing audit log configuration settings.
Note: To manage the DiskXtender service (start, pause, and stop the service, and configure
service startup settings), a user must be a member of both the local Administrators group and the DxAdministrators group.
If the Explorer Add-ons are installed, DxAdministrators can perform the following tasks: • Purge files
• Set retention
• Perform privileged deletes • Enable/disable Direct Read
All members of the local Administrators group are added to this group during DiskXtender installation.
DxUsers Members of the DxUsers group can view the DiskXtender configuration when they log onto the DiskXtender server, either locally or by using a Remote Administrator installation, but they cannot change any settings. In addition, DxUsers cannot view the audit log or view or edit the audit log configuration.
If the Explorer Add-ons are installed, DxUsers can run file reports and view file properties. All members of the local Administrators group and all members of the local Users group are added to this group during DiskXtender installation.
DxSecurityAdmins Members of the DxSecurityAdmins group can view and configure audit log settings on the DiskXtender server. The DiskXtender administration guide provides additional information on viewing and configuring audit logs.
The DiskXtender service account is added to the DxSecurityAdmins group automatically during File System Manager installation.
DxMonitors Members of the DxMonitors group can view the DiskXtender configuration when they log onto the DiskXtender server (either locally or by using a Remote Administrator installation), but they cannot change any settings.
DxMonitors members also can view the audit log file on the DiskXtender server, but they cannot change audit log settings.
Security requirements 33
Auditing system activity
DiskXtender audit logs provide a secure, access-controlled means for monitoring change events to the DiskXtender service, and whether each event succeeds or fails. The audit log enables you to monitor important DiskXtender events, including: ◆ Addition, editing, and deletion of configuration objects (extended drives, media
folders, media groups, rules, and so on) ◆ Media management tasks
◆ Service stops and starts
Audit logging is automatically enabled, and the DiskXtender service account is automatically added to the DxSecurityAdmins group, during File System Manager installation. Similarly, MediaStor audit logging is automatically enabled during installation when the MediaStor service account is added to the MsSecurityAdmins group.
The File System Manager Administrator enables you to configure which events are logged, set a maximum log file size, and change the location where the log file is stored. You can also enable logging of auditing events to the Windows event log in addition to the DiskXtender audit log.
The performance impact caused by audit logging is minimal.
If you use external auditing software on the extended drive, however, there may be a more significant performance impact. Auditing software typically adds a filter driver to the server to monitor access to the file system. This filter amplifies file operation overhead, causing performance degradation. As a result, the use of external auditing software on the DiskXtender server and the extended drive is not recommended.
File Management 35
The following topics provide more information on managing files on a DiskXtender extended drive:
◆ Supported file types... 36 ◆ Migrating files to media ... 40 ◆ Purging files ... 44 ◆ Fetching files ... 47 ◆ Editing files ... 48 ◆ Deleting files ... 49 ◆ Indexing and searching for files... 52 ◆ DiskXtender file management through Windows Explorer ... 54
Supported file types
DiskXtender supports a wide variety of file types. Because DiskXtender does not need to open a file in order to manage it, DiskXtender can manage most file types that can be saved on a Microsoft Windows NTFS volume. However, DiskXtender is designed to serve as an archiving tool for fixed or unstructured data. As a result, adherence to the following guidelines ensures optimal system performance. The most common file types used with DiskXtender include but are not limited to: ◆ Microsoft Office files (.doc, .ppt, .xls, and so on)
◆ Adobe Acrobat files (.pdf) ◆ Text files (.txt)
◆ HTML files (.htm or .html) ◆ XML files (.xml)
◆ ZIP archives (.zip)
◆ Image files, such as JPEGs (.jpg), TIFFs (.tif), bitmaps (.bmp), and GIFs (.gif)
Note: The DiskXtender Search Module can index a majority of the common file types in this list. “Supported file types for indexing” on page 53 provides more information.
Files that are frequently accessed or changed could result in the production of lock files or temporary files. A lock file is a file produced by an application to prevent write access when it is already open by another user. A large number of such files can clog the DiskXtender system or inadvertantly fill the DiskXtender Recycler if it is enabled. Therefore, the following file and data types are not recommended for use with DiskXtender:
◆ Frequently accessed files, such as email files or files in user home directories or temporary directories
IMPORTANT
!
If you must manage these types of files with DiskXtender, then you should use a media type that allows renames and provides faster performance, such as NAS.
◆ Data that is part of a database
◆ Application files for programs installed on the extended drive
Note: Installing applications on or running applications from the DiskXtender extended drive is not recommended.
The following file types are not supported by DiskXtender: ◆ Macintosh files
◆ Personal Folder files (.pst)
If the sixth character in a filename is a tilde and the eighth character is either null or a period (for example, filen~2.doc), then you can save the file to the extended drive, but DiskXtender does not move the file to media. This typically occurs in files with filenames that have been automatically shortened to an 8.3 format.
Supported file types 37
International
character support
DiskXtender can manage files with Unicode characters in either the filename or the file data. However, characters may display incorrectly if the correct language code pages are not installed. In addition, the application that displays DiskXtender logs and reports is not Unicode compliant. Filenames in logs and reports may display incorrectly, even though the file data remains intact.
Some applications used with DiskXtender do not provide the same level of foreign language character support. Table 5 on page 37 lists supported applications with these limitations.
Note: If you use the DiskXtender Search Module to index and search for files on a DiskXtender extended drive and the files include ANSI character encoding, such as Big5 (Chinese) or Shift-JIS (Japanese), then the corresponding code page must be installed and set as the default code page on the ISE server. If a different code page is set as the default on the ISE server, then perform the steps in the EMC DiskXtender Search Module Release 1.2 Release Notes to enable proper indexing and search of the ANSI-encoded files.
You should verify international character support statements for all applications installed on the DiskXtender server before you configure file migration.
Path and filename
length limitations
When you save or edit a file on the extended drive, the full path and filename can total as many as 259 UTF-16 characters. The full path and filename include the following components:
Drive:\Directory1\Directory2\Filename.Extension
where Drive is the assigned volume drive letter, Directory1 and Directory2 are optional folders on the drive, Filename is the name of the file, and Extension is the file
extension.
Note: Japanese path and filenames are limited to 145 characters or less.
DiskXtender does not prevent users from saving a file to the extended drive when the character count for the path and filename exceeds 259 characters. However, files with excessive path and filenames may not be migrated to media, depending on the type of media and the file system with which it is formatted.
Most types of media and media file systems support at least the same number of characters as DiskXtender. However, when writing to media that is formatted with the UDF file system, DiskXtender supports a shorter path and filename of only 127 characters.
Table 5 Product interoperability and foreign-language character support
Product Foreign-language character support
AutoStart Supports only ASCII characters.
NetWorker® PowerSnap™ Supports file system backup if file names and directory names are ASCII characters.
Most NAS file systems support filepaths of 259 UTF-16 characters. However, if DiskXtender is writing to a share on the NAS device, the character count of the full filepath on the device is included in the maximum number of characters allowed. In other words, the total character count includes the path and filename on the extended drive and the full path to the share on the device.
File stream support
File streams contain the data that is written to a file and give more information about a file than attributes and properties. For example, you can create a stream that contains search keywords or the identity of the user account that creates a file. The NTFS file system uses file streams to store private data. Because NTFS supports file streams, many applications now take advantage of file streams to store their data. DiskXtender can manage files with file streams as long as the DiskXtender media supports file streams. All DiskXtender media types support file streams except for some NAS devices. In general, file streams are supported on NAS devices that use Common Internet File System (CIFS) or Server Message Block 2.0 (SMB). If a NAS device is using a different protocol, then consult the device manufacturer for guidance on whether file streams are supported.DiskXtender support for file streams ensures that you can protect all application data in files, not just the primary data. File streams are moved and fetched along with the primary file data. In addition, file streams can be restored from storage media, along with primary file data, for disaster recovery purposes.
Note: You cannot directly read files with streams from media by using the Direct Read feature in DiskXtender. You can set the Direct Read attribute for these files. However, when the file is requested, it is fetched to the extended drive instead of being read directly from the media. In addition, the Direct Read attribute is removed.
If a NAS device configured with DiskXtender does not support file streams, then the file is not moved to media. In addition, a warning message is listed in the event logs to notify you that the file could not be moved to media.
Encryption
DiskXtender can manage encrypted files on the extended drive as long as the files are not encrypted with an on-the-fly encryption (OTFE) method, also called real-time encryption. This type of encryption prevents DiskXtender—specifically the DiskXtender service account—from gaining access to the files to manage them.Microsoft Windows
offline files
DiskXtender supports the offline files feature available in several Windows operating systems. When users access the extended drive, they can configure files or folders on the extended drive as offline files. This enables users to access the files when their workstations are not connected to the network. When the workstations reconnect to the network, any changes that were made to the files are updated on the extended drive.
When you configure a purged file as an offline file, the file is fetched. DiskXtender continues to migrate, fetch, index, purge, and otherwise manage files that are configured as offline files. The files are updated on media and on the ISE server, if necessary, when they are synchronized back to the extended drive and are no longer offline.
Supported file types 39
Microsoft Windows
DFS links
DiskXtender is supported in a Windows Distributed File System (DFS) environment. However, DiskXtender manages only the files that are physically located on the server where it is installed. It does not manage files on other servers that are connected to it by DFS links. For example, the following configurations are supported:
◆ The DFS link is on a server where DiskXtender is not installed (Server A), and the link points to an extended drive on a server where DiskXtender is installed (Server B).
Users can use the DFS link on Server A to access the files on Server B, even if the files have been purged.
DiskXtender manages only the files on Server B.
◆ The DFS link is on an extended drive on a DiskXtender server (Server A), and the link points to another server (Server B).
Users can use the DFS link on Server A to access the files on Server B.
The DiskXtender installation on Server A manages all of the files that are saved locally to its extended drive. However, it does not manage the files on Server B.
CAUTION
!
DFS is supported only in DFS nonreplication mode. Attempts to use DiskXtender with DFS replication enabled might cause data loss.
Migrating files to media
The term file migration refers to the function of moving files from a local hard drive to one or more pieces of storage media.
In DiskXtender, a move is actually a copy. When DiskXtender moves a file to media, it is really copying the file data out to media and adding extended attribute information to the file on the drive. The file is then managed by DiskXtender, and the data resides both on the extended drive and on the media.
File migration
models
You can migrate files to media through DiskXtender by using one of three file migration models:
◆ Standard migration — Each file is migrated once from the extended drive to a piece of media, as shown in Figure 4 on page 40.
Figure 4 Standard migration
◆ Multi-target migration — Each file is migrated from the extended drive to multiple targets (pieces, and even different types of media), as shown in Figure 5 on page 40.
Figure 5 Multi-target migration
Multi-target migration provides improved data availability and reliability. In the
GEN-000936 File Media Extended drive on DiskXtender server GEN-000937 File Tape Extended drive on DiskXtender server Disk array
Migrating files to media 41
◆ Tiered migration — With tiered migration, also called hierarchical storage management (HSM), each file is migrated twice: from one extended drive to another extended drive, and then from that extended drive to tape media, as shown in Figure 6 on page 41.
Figure 6 Tiered migration
To accomplish this through DiskXtender, media folders on the second extended drive are configured as Aggregate NAS media. The files from the first extended drive are migrated to the Aggregate NAS media. DiskXtender then moves the files from the Aggregate NAS media to tape media.
When files are saved to a media folder on the first extended drive that contains a media group with Aggregate NAS media, DiskXtender does not allow you to rename files or folders on the first extended drive. This restriction mimics the behavior of the second extended drive (the Aggregate NAS media), because the second extended drive is writing to tape, which also does not allow file or folder renames.
The restrictions of Aggregate NAS media are designed to ensure that files and file tags on both extended drives remain synchronized, and that the files on the subsequent tape media are not orphaned.
Tiered migration is only supported through the use of the Aggregate NAS media type and tape media. DiskXtender does not support tiered migration from one extended drive to another media type (such as EMC Centera) before a final migration to tape. Migration from Aggregate NAS to media other than tape (such as EMC Centera or optical) is also not supported.
GEN-000938
File Tape
Extended drive on first DiskXtender server
File
Extended drive on second DiskXtender server
Customizing file
migration
DiskXtender automates the migration of files to media by using a rule-based system. You can customize this rule-based system very specifically to determine which files are moved, what media they are moved to, and when. This customization is accomplished through the File System Manager Administrator by:
◆ Organizing files on the extended drive into media folders
◆ Grouping media into media groups and assigning it to media folders ◆ Configuring move rules that identify which files should be migrated ◆ Scheduling a window of opportunity when file migration can occur
Media folders Media folders help to organize files on the extended drive. These folders are created as physical folders (or subfolders) on the extended drive, and can be viewed as such through Windows Explorer.
You can create a media folder by using a folder that already exists on the extended drive. Alternatively, you can create a new physical folder on the drive for the media folder.
Files on the extended drive can be stored in a single media folder, or they can be divided into multiple media folders. The creation of separate media folders enables you to segregate the data on both the extended drive and the storage media.
When a file is written to a piece of media, the directory structure on the media mirrors the extended drive directory structure. The root media folder, however, does not appear on the storage media. For example, if the Reports media folder is located at the root of extended drive E, then E:\Reports\Accounts.doc on the extended drive is stored as Accounts.doc on the media.
Media groups Media groups are specific groupings or pools of media that have been assigned to a media folder. Files in the media folder are written to media in the media groups for the media folder.
Media groups provide several options that control the way files are written to the media in the media group. For example, you can specify whether files are written to each piece of media sequentially or randomly:
◆ With the sequential media fill method, each piece of media is filled with files based on the order in which the media is listed in the File System Manager Administrator. This fill method optimizes file retrieval performance and is designed for removable media.
◆ With the random media fill method, files are written to media as the media is available. This fill method optimizes file migration performance and is designed for NAS, EMC Centera, and TSM media.
It is also through media groups that you can configure automated labeling and compaction for removable media, as well as automated virtual media creation for EMC Centera.
A special kind of media group, called a multi-target group, enables implementation of the multi-target migration model. A multi-target media group is designed solely to contain media targets, which are two, three, or four standard media groups that contain the media to which you want to write files. You cannot assign individual pieces of media to the multi-target group, and there are no options or automated media management features. The options and automated media management
Migrating files to media 43
When using multi-target media groups, you can define an expiration policy for each target media group. When a file meets the expiration criteria for a target media group, it is deleted from the media in the group. However, the file remains on media in other target media groups until it meets the expiration criteria for those groups. The expiration polices enable you to reclaim space on some pieces of media while leaving files active on other pieces of media.
Move rules Move rules contain the criteria that DiskXtender follows when choosing which files to move to a particular media group.
There are two types of move rules:
◆ Inclusive — Creating an inclusive move rule specifies which files should be moved, and which target group of media (either a standard or multi-target media group) will be used to store them.
◆ Exclusive — Creating an exclusive move rule specifies which files should not be moved to media.
You must create at least one inclusive move rule to move files to media. You can configure how each rule selects files to be moved or excluded from movement based on the location of the file (media folder or subfolder), extension, attributes, and size. You can also configure the media group to which the move rule points, as well as an age delay for moving files, preventing DiskXtender from moving them until a specified time period has elapsed after each file was created, last accessed, or last written to (edited).
If you are using EMC Centera, Celerra with the FLR file system, or a NetApp NAS device with the SnapLock software, move rules can also be used to set retention for qualifying files. When a file qualifies for a move rule that contains a retention period, you cannot edit or delete the file until the retention period expires.
By default, files qualify for move rules when they are saved to the extended drive. If the move rule contains age delay criteria, then the file is qualified for move rules during a background scan.
A background scan is a scan of the extended drive. This scan is performed so that the files on the drive can be qualified against the rules (including purge, delete, and index rules) for each media folder. Background scans allow DiskXtender to verify that all files on the extended drive that need to be managed are being managed.
By default, background scans begin automatically at midnight each night and run only once in a 24-hour time period. However, you can change the time and frequency at which background scans occur to maximize system performance. You can also force DiskXtender to perform a background scan any time one is needed by right-clicking the extended drive and selecting Force Background Scan.
Scheduling file migration
When files qualify for migration based on move rules, those files are written to the move list for a media group. The move list is a list of files that need to be migrated to the media in the media group.
The move list is only processed, and files are only moved to media, when the Move Files to Media schedule is active. The Move Files to Media schedule specifies a time period during which file migration can take place.
By default, the Move Files to Media schedule is active from 8 p.m. to 9 a.m. However, you can adjust the schedule to maximize system performance. File migration can negatively impact file retrieval performance, so it should occur during the times of least activity.
Purging files
When DiskXtender moves files, it really copies the files to storage media. In other words, the file data exists on both the media and on the extended drive.
When DiskXtender purges a file, it removes the file data from the extended drive and leaves behind a file tag on the extended drive. A file tag contains information about the file, including name, size, age, retention period (if applicable), and other attributes.
Purging files frees space on the extended drive, while maintaining the appearance that the files are still on the drive. Table 6 on page 44 provides details on file icons for unmanaged, fetched, and purged files.
A purged file is still accessible, and to a user machine, appears to reside on the extended drive. When the user requests the file, DiskXtender performs the following actions:
1. Accesses the media where the file is stored. 2. Retrieves the file data.
3. Displays it for the user.
When a file has been migrated to a single piece of media, a file tag consumes between 0 bytes and 1 cluster of disk space. (On Microsoft Windows NTFS systems, a cluster of disk space averages approximately 4 KB, although the size depends on a number of variables.) When a file has been migrated to multiple pieces of media through multi-target migration, then a file tag is likely to consume 1 cluster of disk space. Because space and file retrieval requirements vary, DiskXtender provides several different ways to purge files from the extended drive, enabling you to be very specific as to when files are purged from the extended drive.
Files cannot be purged from the extended drive until they are moved to media and indexed, if indexing is enabled. However, once a file is moved to media, you can choose whether to automatically purge that file from the extended drive:
◆ Immediately after it has been moved ◆ When extended drive space is low
◆ During the next background scan (after the file qualifies for a purge rule)
Table 6 Icons for files on the extended drive
File type Icon
Unmigrated and fetched file
Purged file (file tag) in Windows Vista and Windows Server 2008
Purging files 45
There may even be some files that you do not want to purge at all.
The purge options you choose are likely determined by a number of factors, including:
◆ The type of storage media you use
◆ How much space you have on the extended drive ◆ How often files are accessed
◆ How long files are normally active
For example, if the files on the extended drive are accessed frequently for a certain number of days after they are created, you should wait to purge the files until they are no longer needed.
Purge rules
A purge rule contains the instructions that DiskXtender follows when choosing which files to purge from the extended drive and when.
Purge rules are necessary if you want to purge files as disk space is needed or during background scans.
As with move rules, there are two types of purge rules:
◆ Inclusive — An inclusive purge rule enables you to specify which migrated files should be purged from the extended drive and when.
◆ Exclusive — An exclusive purge rule enables you to specify which moved files you do not want DiskXtender to purge.
You can configure how each rule selects files to be purged or excluded from purging based on the location of the file (media folder or subfolder), extension, attributes, and size. You can also configure an age delay for purging files, which prevents those files from being purged until a specified time period has elapsed after the file was created, last accessed, or last written to (edited).
Purging files as disk space is needed
You can set up purge rules so that DiskXtender purges files only when disk space is needed. The following process occurs for each file that is managed by DiskXtender: 1. When files qualify for a purge rule (during a background scan), DiskXtender adds
them to the purge list.
2. As additional files are written to the extended drive and the amount of used space on the extended drive reaches a certain percentage (the purge start watermark), DiskXtender begins purging the files that appear on the purge list.
3. DiskXtender continues to purge files until the percentage of used space is reduced to an acceptable level (the purge stop watermark).
You can customize the purge watermarks for each extended drive. By default, the purge start watermark is set to 95 percent, and the purge stop watermark is set to 90 percent.
Because the purge list is processed only for as long as is necessary to free up space to the purge stop watermark, you can also configure the priority for files added to the purge list. Priorities can be used to ensure that certain files, such as larger files or files that are accessed less frequently, are purged first (when disk space is needed), which optimizes the purge process.
The purging of files in this way ensures that file data remains on the extended drive until purging to recover space on the extended drive is absolutely necessary. Maintaining file data on the extended drive can improve performance because it helps minimize fetch requests.
Purging files during background scans
Files qualify for purge rules during a background scan. You can set up the purge rules so that DiskXtender purges files as soon as they qualify for the purge rules.
This purging option helps to maintain a high volume of free space on the extended drive.
Note: Files may be purged before a background scan takes place (regardless of purge rule settings) if disk space is needed before the next background scan starts.
Purging files immediately after migration
You can purge files immediately after they are moved to media by using a move rule option.
You may want to use this purge option to target certain files for movement to media and immediate purge.
IMPORTANT
!
Even if you plan to purge files immediately after they are moved by using the move rule option, you should still configure purge rules. If you do not configure purge rules and the purged files are fetched, the files may not be purged again.
Purging files during DVD-R finalization
If you use DVD-R media, you cannot purge files until the media they are written to is finalized. When you finalize the media, you can choose to purge all files that have been written to that media.
If you do not choose to purge files as a function of finalization, the data for those files remains on the extended drive until the files qualify for configured purge rules. Then it is the selections made in the purge rules that determine when the files are purged from the extended drive.
Fetching files 47
Fetching files
If a user attempts to access a file on the extended drive that has been migrated to media and purged, the file is retrieved from the media and copied back to the extended drive. The user can then open the file on the extended drive. The retrieval of a purged file from media is called a fetch.
If the environment is a multi-target migration environment, purged files are fetched from the first target media group that is listed under the multi-target group. You ca
